Program-transmission system for apartment houses



' July 10,1928. 1,676,301

J. F. TOOMEY PROGRAM TRANSMISSION SYSTEM FOR APARTMENT HOUSES Filed Sept. 20, 1924 5 Sheets-Sheet 1 I I l I. I l I l l ,3 i. Ks

INVENTOR 6' ATTORNEY -Jul 10, 192s, $616,301

J. F. TOOMEY PROGRAM TRANSMISSION SYSTEM FOR APARTMENT HOUSES Filed Sept. 20, 1924 ifa'Sheets-Sheet INVENTQR JED/92% I K 6 ATTORNEY July' 10, 192 8; 1,676,301

I I j J. 'F. TOQMEY I 'fROGRAM TRANSMISSION SYSTEM FOR APARTMENT HOUSES Filed Sgpt. 20, 1924 s Sheets-Sheet a I IINVENTOR y WK ATTORNEY JOHN E: 'TooME'Yf oF -mweesz; i};

TELEGRAPH co raswir oarommoaor uuw YORK.

raoemmimizausmssmn 's szsrnir FUR APARTM'ENT Houses AppmafimmeiSe tember 20, 1924: Serial No. 738,923:

, This invention relates to transmission systems; and more particularly toa system for the distribution of programsgsuch its-news, mus1c= and eiitertainments houses and the like.

It has'been proposed'totransmit enter-' tainlnentprograms-over Wiresby telephony;

I to subscribers; and in the caseof-a la'rgefl city; where 'apartment houses'abound,the an programwould betransmitted' over xa trunk-c or trunks from a studio-to -cent raloffices,

such as telephone exchanges: 1 At eacl cen tral oliice branch trunks would extend fro'm each central o'fficeitrunk to'various*apartnient houses in the neighborhood; .Atxthe apartment house the trunk would be aga nbranched wvlth new lines eXtend1ng-to=-each subscriber. g

In such a: system it would-be desirable' to a have amplifiers at. eaclr, branching point such as the central ofiice and-theapaitment house. It is also desirable that the attend ant at the studio shouldexercisesupervisory: control over the entire circuit including; the

branching "points.

in accordance with the rpresent inventionythe circuit for controllingythe' filament and 1\ plate circuits of the: various: amplifiers iS'- Vided? toenable the attendant to render; the 7 circuit operative oriinoperative at: will] controlled by meansof an alternating-cm rent. .The ,mo'tor' generators for' supp-lying thecurrenufor the amplifiers are also startedand'stopped under the control of an attendunt at the studio by ineansrof' alternat cuit is provided Whiclrindi'cates to-theat-v tendant at 'the' studio Whether thetransmission circuit is functioning: properly; or;

., ,whether there is any trouble at some point;

trolled'by direct'current. Another feature of the-inventionresides in the 'factthatdurin the time that the-transmission circuitisi ;functioning normally noslgnahng curre'nt flows'over the' circuit. s The invention may noW be t more fully un'-:

derstood vfrom the following description;-

when readjin connection with the accomembodiment otth'einventi'on';

Referringto the drawing-(Fig. T

'to-Q apartment I I :bebranched from the output of the amplifierlA- its-indicated; At each-central office" i (Fig; 2), the trunksuch-as T -is providedvfi With an additional amplifying:equipment; A- -.co;rnprising vacuuml tubes- 10'; ll; 'iand 12:. On theout-, put side ot'each amp-lifier such*'asA each trunk'isuch as Ti is-branched into branch trunks such as T2, Whichlead to apartment houses. Ari-amplifying equipment: such: as"

at the apartmenthouse. (Fig. l). m pl-i-fying equipment A as illustrated ,coniprises vacuum tubes 20,21 and 22,,together with associated circuits. v

A -1notor generatorCset MG; is provided branches and over the amplifying-or other equipment associated with l the" various tliedetails of-these sets. form nopartofthe present invention, theyare merely illustrated schematicallyg' At-the-studio a control-.

" ing current. In addition;-a signalingscir;

' This signaling: circuit is preferably? con'fnaies a trunk .extending' tronr a studio to aoentral ofiice. At the studio anlampli- ,-Assicruorri:o' Al /reamin EL-emanate fier scl'lematically indicated at] A" is provid ejd and the various trunks such as T ex-- tending; to the difie rent central oflices' Will and their associated circuits;

A; is associated with each trunk suchas 3T at the apartmentlhouse vfor supplying' the; plate andfilament culrrent to-operatefthes operating vacuum tub'es 10. 11 and .12. As

lingjack J and a-controllingjkeyK are-pro-- 'vaouumtubes'QO; 21, 22. .At the' centralfi I oflice asimil-arfmotor generator set, MG ylis' provided for supplying the plate current for} 80 Signal lampsmr other-devices are also "pro vided to indicate to dition of the circuit.

ant at thestudio desires to-transmit pro conductor 25 to render-the amplifier atthe studio operative in the Well-known -manner.

The attendanti then momentarily depresses the key; "K {to connect alternating; current overits leiftdiand contact totheniidpoint of I the transformer Winding associated 'Wltl'l; the trunk T The alternating current fio-Ws over'the two sides "of the-trunk T1 inwparal the'attendant thGfZOll-Q v i 90 Furtherdetails of the inventioniwill now be clear from thedesC'riptiOn; of the opera- 1 tionpvhich .isas follows: when the attendlel anchthrough the winding'of alternating (ill - each trunk, such as T t shunted by a non-inductive connection, howunitted from the trunk T and at its front contact applies alternating currentto the bus-bar 26. From the bus-bar the alternating current flows from the various third wires associated with the trunks such asT leading to the apartment houses. A relay, suchas C is interposed in the connection between the bus-bar 26 and the midpoint of the transformer winding associated with This relay is ever, so that the alternating current does not operate the relay. The alternating current now flows over the two sides of the trunks, si'ichasT in parallel and thence through an alternating current relay AC at the apartment house. It will therefore be seen that the alternating current relays AC at the central oilice and A6, at the apartment house are energized simultaneously during thetime that the key K at the studio is depressed.

Returning to the central ofiice, the relay AC upon being energized, also completes a circuit from ground over its front contact, over the right-hand back contact of relay L and through the winding of slow-release relay SR, to battery. The relay SR, is now energized and as soon as the key K is restored at the studio, relay AC, releases and F closes a circuit from ground over its back contact, over the front contact of slow-release relay SR, and through the windings of relays L and F to battery. Relay L at its right-hand front contact disconnects slowrelease relay SR but before the latter has become deenergized, the relay L establishes a locking circuit for the relays F, and L over the left-hand front contact of relay L to the back contact of slow-release. relay SR,.

Relay F upon being energized, completes a filament circuit for tubes 10, 11 and 12 from ground over the inner front contact of relay F through the filaments of tubes 10, 11 and 12 in series, and thence to the 24-volt battery so that the filaments of the amplifier tubes begin to glow. Relay F also connects ground over its outer front contact to the winding of relay X, which starts motor gen.- erator set MG, into operation. At the same time a signaling circuit for the studio is established from ground over the outer front contact of relay F, to conductor 27 and thence over the back contact of relay P to I conductor 28. A connection also extends from conductor 27 to conductor 28 over the back contacts of relays l, and Y, in parallel, over conductor back contacts of various trunk relays, such as C in series, and thence over conductor 80 to conductor 28. From conductor 28 the signaling trunk extends through the winding of the relays S, to the midpoint of the winding of the tran former associated with the trunkT,, over the two sides of the trunk in parallel, and thence over the normal contact of the key K at the studio, through the winding of relay S and over the make contact of the jack J to battery. Relays S and S, are energized over the circuit above traced and remain energized until the apparatu. a all in operating condition, as will be described later.

Relay S, on being energized, completes a circuit from ground, over its front contact, through the right-hand winding of the relay L and through the winding of the relay M, and thence over the make contacts of the jack J to battery. Relay M temporarily closes the circuit of an alarm signal and a buzzer, while the apparatus associated with the various amplifiers is being placed in operating condition, as will be deicribed later. Relay L completes a locking circuit from ground through its left ending, over its inner front contact to battery, over the make. contacts of the jack J. The relay L will therefore remain locked up so long as the con nection is established.

Returning again to the central office, as soon as the motor generator set MG, is set into operation and generates the necessary plate voltage, the relay P is operated and opens the connectionbetween conductors 27 and 28 at one point. At the same time the plate current of the tube 10 begins to flow through the winding of the relay 1, and the plate current of the tubes 11 and 12 begins to flow through the winding of the relay Y, and these two relays are therefore energized and open connections between conductors 27 and 28 at another point.

If, at this time, all the trunk relays, such relays, such as C are all energized during the timethat the amplifying equipment and motor generator sets at the apartment house are being put into operation. The contacts of each of these relays are so arranged as to independently place ground upon the conductor 30 so that the signaling circuit traced through conductor 28 and relays S, and S will be maintained independently of the de energization of relays P 1, and Y, until such time as all the trunk relays are released. 7

Going now to the apartment house, it will be remembered that during the time that the key K was depressed to transmit alternating current, the relay R at the central oilice was energized to transmit alternating current to the alternating current relay AC so that the latter relay is energized during groundo'ver its front contact, over the righthand back contact or relayL and through the Windingoi' slow-release relay'SR, to battery. 'VVhen the alternating current ceases to flow, relay'Ac -releas'es and comcontact, over the front contact of relay SR through the windings of relays L and F to battery. Relay L; at its right-hand contact' releases relay SR; and atits left-hand contact'coinple'tes a locking circuit for the relays -L an'd'T over theback contact ofrel'ay SR Relay F upon being energized, at its outer front contact connects ground through the Winding of relay X Which,'upon being energized, sets the motor-generator set *MGr into operation to generate the plate and filament voltage;

It Will be noted that ground is normally applied tothe conductor over the back contactsof relays P and P Consequently, assoon as 'relayR at the central oiiice-releases its ari'nature (which occurs at thecessation of transmission of alternating current theinner front contact "of relay F through from the studio to disconnect the, alternating current from the "circuit through the trunk relays such as 'C' aeircuit willbe completed for the-trunk relays such as C asfollows: from battery, over the front contact of relay Z over the back'contact of relay. R bus-bar 26, through the 'win'ding of trunk're lay'C over the'tWo sides'of the/trunkT'- in parallel, through the Winding'of relay- S overconductor 35; and thence'to ground over the back'contacts of relays P and P r Relays S and C are energized over the 'circuits above traced and in 'a similar man-- tor 35.

WVhen the motor generator set MG, is

started,into'operation by the relay X relays P-"',,; and P, will be energized as soon as the plate and filament'voltages, respectively, at-' tain theproper values. The energization'of 1' these relays disconnects ground from the conductor-35 at their contacts." The filament circuit'is now completed from' ground, over the filament on tubes 20, 21 and 22to the 24-volt terminal of the motor generator'set.

The tubes now begin to glow and the space current flowing througlrthe tubes from the- 350' volt terminal of the motor generator set energizes relays L and'Y thereby removing grou'nd-"from conductor 32 at their contacts.

All of the ground connections to conductor 35 having'now been opened, the circuit previously traced through relay; S, and trunk relay: C is open sothat these relays are-deenergized. Similar operations take place in} connection with all the other trunks leading to the apartment houses and it will beobf served that eaeh'of thetrunl; relays is enerpletesacircuit from ground over its back gized as soon as alternating signaling "cur rent ceases and remainsenergized until the motor generator setsand the amplifier sets associated avitheach trunk are putiinto operati'ye'condition; It illalso be'noted that] as soon" as the apparatus associated with each trunk is placed-in operative condit-romso "the"corresponding tru'nlcrelay is released.

It Will be remembered thatground is a'p-- plied to conductor3O at the central oliice as soon as anytrunk relay isyenergized. As

soon, howe er, as all of the trunk relays have I been. released, the ground is removed from conductor 30, and in tlie me'antime the motor generator 'MG and the amplifier A at the central otlice have been"placed -in op' erative condition so that relays P I, and'QG Y, are energized. Consiequentlyjall possible groundconnectionswill have beerr're moved irom conductor 28 and the direct 'cu'r' rent" signaling circuit through relay S at v the central oliice and relay S at the stutli'o will be open, tlierebyreleasing relays Sand S telay S at the studio as energized" during the brief period that it required Y place all of the, amplifiers and inotor gen-' erator sets of all'th'e circ'uits'ni operative condition, and during thisbri'ef per'iod the circuit maintained through the're lay M over the left-hand front 1 contact of relay S caused; the momentary operation of the alarm signal and buzzer at the studio. As soon as relay S is released, however, the alternating signal and-buzzer ceasesand a circu tis completed from ground over the left-hand back contact of relay S and over 'theouterffront con tact of locked up relayL through 'the'O. Kb r signal lamp to battery at the contacts of the jack J. All of the apparatus is n'owin operative condition, and this factis ind-i cated to the operator by the O. K. signal,

sothat the program transmission may now 51 begin. I

It trouble should occur in connection with any or the amplifyingapparatus or motor generator sets associated With the various branch trunks, the relay S Will againbe energized"to open the circuit of the 0.1K. signal and close the circuitof the relay M to continuously actuate the alarm signal and the buzzer. For example, if the motor generator set MG, should be disablechthe relay P Would be released and ground would be applied to conductor 28 over the outer front contactot relay F and overjthe b'aclr'contact, of relayP Similarlyg'if'the space current'should-cease to flow for any reason necting ground to conductor 35.

sequent deenergizatiou of relays I and Y,.

The application of ground to conductor 28 under any one or all of these conditions, immediately completes the circuits for relays S and S, as previously traced, so that the .alarm signal and the buzzer will be actuated and continue in operation as long as the abnormal condition remains In case the motor generator MG at the apartment house should fail, relay P or P,, or both, would be released, thereby conlf a filament of one of the amplifiers should fail, or if for any other reason the plate current of any one of the three vacuum tubes of the.

amplifier A, should cease to flow, relay 1,, or Y or both, would be released and apply ground to conductor Under any of these conditions the circuit for relay S and the trunk relay C will again be completed, thereby connecting ground from the front contact of the trunk relay to the conductor 30 and thence to the conductor 28. This would in turn complete the circuit for relay S at the studio and cause the actuation of the alarm signal and buzzer.

At the end of the program the attendant at the studio may restore the circuit to its normal condition by momentarily actuating the key K to connect alternating current over the two sides of the trunk T to enerthe alternating current relay AC Relay AC upon being energized, completes a circuit from ground over its front contact and o'er the right-hand front contact of locked-up relay L and through the winding of slow-release relay SE, to battery. ltelay S t upon being energized, completes a new locking circuit from ground over the front contact of relay AC over the righthand front contact of relay T1,, over the lower front contact of relay SEQ, over the left-hand front contact of relay L and through the windings of relays L and F to battery. As soon as the relay AC releases, however, the locking circuit above traced is opened and relays F and L, are released. The relay SEQ, being slow to release, does not release its armature until the relays L and F, are restored to normal, with the consequent opening of the normal circuit of the relay SR, at the right-hand contact of relay L,.

Relay F upon being released. opens a filament circuit of the tubes 10, 11 and 12 at its inner contact, and at its outer contact,

and disconnects ground from relay X so that the operation of the motor generator set MGr ceases. The relay P is accordingly released and relays Y and T are released as soon as space current ceases to flow through. the vacuum tubes. No ground is connected to the conductor 28, however, by this operation, the ground connection over the contacts of relays P Y and T is controlled by the outer contact of relay F which is re leased. The apparatus at the central station is therefore restored to normal. The release of F also disconnects ground at its outer contact from the conductor 27 and consequently from the winding of the relay 2,, which is accordingly released.

Returning again to the relay AC which was energized while the key K was de- 1 pressed, it will be observed that a circuit was completed over the front contact of the relay- AC through the winding of the relay R The relay R is accordingly energized and connects alternating current to the busbar 26 so long as the key K remains depressed, consequently alternating current is transn'iitted over the front contact of the relay R over the bus-bar 26, over the two sides of the trunk T in parallel and thence to the relay AC energizing the latter relay. Relay AC upon being energized, completes a circuit from ground over its front contact, over the right-hand front contact of relay L and through the winding of SR to battery. A new locking circuit is now established for relays F and I L from. ground over the front contact of relay AC over the right-hand front contact of relay L over the front contact of relay SR over the left-hand front contact of relay L and through the windings of relays L and F to battery.

As soon as the key K is restored, with the consequent release of relay R the alternating current ceasesto flow through relay AC The locking circuit previously traced for the relays L and F is now open, and these two relays are restored to normal. The circuit of the relay SR is also open at the contact of the relay AC so that relay SR, is re stored to normal a moment later. As soon as the relay F releases, the filament circuit of the tubes 20, 21 and 22 is opened at the inner contact of the relay F The space current accordingly ceases to flow through the tubes and the relays Y and 1 are released. This operation does not result in applying ground to conductor 35, however, as the ground connection is open at the outer contact of relay F The opening of this contact also releases the relay X which causes the motor generator set MG to cease functioning. The relays P and P are now released and connect ground to conductor 35. This does not result in the energization of relay S and the trunk relay C however,

for the circuit of the trunk relay C is held open at the contact of released relay Z The apparatus is now all restored to normal as a consequence of a momentary transmission of alternating current by the depression of the key IE, and this occurs Without the establishment of any direct current signaling circuit to actuate relay S after the key K has been released. The attendant noW removes the dead plug from the jack J to release the locked-up relay L and disable'the amplifier A, so that all the apparatus is now in 'its normal condition. l

It will be obvious that the general principle herein disclosed may be embodied in many other organizations Widelyditterent from those illustrated Without departing from the spirit of the invention as definedv in the following claims. i

WVhat is claimed is:

1. In a signaling giystem, a trunk, a norsaid trunk, to render saidamplifier operative, and means responsive to the subsequent transmission of alternating current over sald trunk to disable said amplifier. I

3. In a signaling system, a trunk, an amplifier associated with said trunk normally inoperative means for supplying current for said amplifier, and'switching means unresponsive'to voice currents but responsive to the momentary transmission of low frequency alternating current over said trunk to render said current supply means operative. i. In a signaling system, a trunk, an amplifier associated With said trunk, normally inoperative means for supplying current for said amplifier, means responsive to the momentary transmission of alternating current over said trunk to render said current supply means operative, and means responsive to the subsequent transmission of alternating current over said trunk to render said current supply means again inoperative.

5. In a signaling system, a trunk, a nor-' mally disabled amplifier associated with said trunk, means responsive to the transmission of alternating current over said trunk to render said amplifier operative, and means responsive to the momentary transmission of a direct current over said trunk to indicate the condition of the apparatus associated with said trunk.

6. In a signaling system, strunlt, a new mally disabled amplifier associated with said trunk, means: responsive to the momentary transmission of alternating current over'said truck't-o render said amplifieroperative, and

means responsive to the nmmentary transmission of a direct current over said trunk to indicate the condition of the apparatus" associated with said trunk 7. In a sign'alingsystem, a trunk, anor-' mally disabled amplifier associated with said truck, meanswresponsive to the momentary transmission of alternating current oversaid trunk to render said amplifier operative,- means' responsive to the subsequent trans mission of alternating current overi said" trunk to disable-said amplifier,'and means responsive to the momentary transmission of a dlrect current over said trunk to indicate the condition of the apparatus associated with said'trunk. i

8. Inasignaling system,atrunk, an em: plifier associated With said trunk, normally inoperative: means for supplying currentfor said amplifier, means responsive to the trans mission of alternating,' current over said trunk to render said current supply means} operative, and means responsive to the inomentary transmission of a direct current over said trunk to indlca'te the condition'of the apparatus associated with-said trunk. 9. In a signaling system, a trunkpanami plifier associated with said trunk, .norma'lly inoperative means for supplying current for said amplifier, means responsive to theme mentary transmission of alternating current over saidtrunk to render said current supply'meansi operative,and means responsive tothemOm'enta'ry transmission of a direct current over said trunk to indicate the condition of the apparatus associated With said trunk.

10 In a signaling system, a trunk, an amplifier associated With'said trunk, normally inoperative means for supplyingcurrent for said amplifier, means responsive to the moinentary transmission of alternating current over said trunk to render's'aid current supply means operative, means responsive tothe subsequent transmission of alternating current over said trunk to render said cur rent supply means again inoperative, and means responsive to the momentary transmis sion of a direct current oversaid trunk to indicate the condition of the apparatus a sociated With said trunk.

11. In a signaling system, a trunk extendmg from a main stationto an outlying station, a normally disabled amplifier associated with said trunk at said outlying station, branch trunks extending from said outlying stations to a plurality of local stations, nor finally disabled I amplifiers associated with the branch ticinks at each local station, and responsive tov the transmission ai means responsive to the momentary transmission of alternating current from said mam station to render all of said amplifiers operative.v

13. In a signaling system, a trunk extending from a' main station to an outlying station, a normally disabled amplifier associated With said trunk at said outlying station, branch trunks extending from said outlying stations to a plurality of local stations, norfiers associated mally disabled amplifiers associated With the branch trunks at each local station means responsive to the momentary transmission of alternating current from said main station to render all of said amplifiers operative, and means responsive to the subsequent transmission of alternating current from said main stationto again disable all of said amplifiers.

14. In a signaling system, a trunk extending from a main station to an outlying station, an amplifier associated with said trunk, branchtrunks extending "from said outlying station to a plurality of local stations, ampliith said branch trunks at each local station, normally inoperative means at each station to supply current to the amplifier thereat, and means responsive to the transmission of alternating current from said main station to renderthe current supply meansat all 01 said stations operative.

15. In a signaling system, a trunk extending from a main station to an outlying station, an amplifier associated with said trunk, branch trunks extending from said outlying station to a plurality of local stations, amplifiers associated With said branch trunks at each local station, normally inoperative mean at each station to supply current to the amplifier thereat, and means responsive to the momentary transmission of alternating current from said main station to render the current supply means at all of said stations operative.

16. In a signaling system, a trunk extending from a main station to an outlying station, an amplifier associated with said trunk, branch trunks extending from said outlying station to a plurality of local stations, amplifiers associated with said branch trunks at each local station, normally inoperative means at each station to supply current to the amplifier thereat, means responsive to the momentary transmission of alternating current from said main station to render the current supply means at all of said stations operative, and means responsive to the subsequent transmission of alternating current from the main station to again disable said current supply means.

In testimony whereof, I have signed my name to this specification this 19th day of September 1924.

JOHN F. TOOMEY. 

